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Experiments were done on the inhibitory synapse of crayfish tonic muscle receptor organs (MROs) to determine whether gamma-aminobutyric acid (GABA) receptors would be affected by denervation or axotomy. It was found that severing the dorsal nerve containing the MRO sensory and inhibitory neurons usually induced, in 30 days or less, a dramatic transformation in the responses of MROs to ionophoretically applied GABA. In contrast to normal MROs which show only inhibitory responses to GABA, transformed MROs were substantially depolarized and excited by GABA application to numerous points found on the axon, soma, dendrites. Interspersed among the points of excitation, normal inhibitory points could still be found on the transformed cells. The results suggested that chronic lesions can induced structural changes in GABA receptors, whereby the Cl- ionophore is replaced by a cationic channel. It was possible to compare the effects of postsynaptic axotomy alone with those of postsynaptic plus presynaptic axotomy by testing MROs from animals whose ventral nerve cord was sectioned. These experiments suggested that interruption of the presynaptic neuron is an important factor in the transformation. It was not determined whether complete degeneration of the inhibitory synapse is necessary for the transformation, but the rapidity of the effect, coupled with the probability of long-term survival of synaptic contacts, suggested that complete degeneration was not necessary. Similarities were found in the GABA responses of transformed MROs and those MROs which normally receive no innervation, which are located in the sixth abdominal segment. These results support the idea that trophic regulation from inhibitory neurons is a factor in stabilizing the association of the Cl- ionophore with GABA receptor. 相似文献
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Basic fibroblast growth factor requires a long-lasting activation of protein kinase C to induce cell proliferation in transformed fetal bovine aortic endothelial cells. 总被引:5,自引:1,他引:4 下载免费PDF全文
M Presta L Tiberio M Rusnati P Dell''Era G Ragnotti 《Molecular biology of the cell》1991,2(9):719-726
Basic fibroblast growth factor (bFGF) induces a protein kinase C (PKC)-dependent mitogenic response in transformed fetal bovine aortic endothelial GM 7373 cells. A long-lasting interaction of bFGF with the cell is required to induce cell proliferation. bFGF-treated cells are in fact committed to proliferate only after they have entered the phase S of the cell cycle, 12-14 h after the beginning of bFGF treatment. Before that time, the mitogenic response to bFGF is abolished by 1) removal of extracellular bFGF by suramin, 2) addition of neutralizing anti-bFGF antibodies to the culture medium, 3) inhibition of PKC activity by the protein kinase inhibitor H-7, and 4) down-regulation of PKC by cotreatment with phorbol ester. Thus the requirement for a prolonged interaction of bFGF with the cell reflects the requirement for a prolonged activation of PKC. Similar conclusions can be drawn for the PKC activators 12-O-tetradecanoyl phorbol 13-acetate and 1,2-dioctanoyl-sn-glycerol. The two molecules require 16 and 6 h, respectively, of activation of PKC to induce 50% of maximal cell proliferation. The requirement for a long-lasting activation of PKC appears to be a mechanism for the control of cell proliferation capable of discriminating among transient nonmitogenic stimuli and long-lasting mitogenic stimuli. 相似文献
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Marrucci Luca Iraldo Fabio Daddi Tiberio 《The International Journal of Life Cycle Assessment》2021,26(3):575-590
The International Journal of Life Cycle Assessment - The EU Ecolabel is a voluntary scheme that aims to reduce the overall environmental impact of organisations to boost sustainable consumption in... 相似文献
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Perini P Tiberio M Sivieri S Facchinetti A Biasi G Gallo P 《European cytokine network》2000,11(1):81-86
BACKGROUND: interferon beta (IFN-beta) reduces relapse rate and disease progression in patients with the relapsing-remitting form of multiple sclerosis (RRMS). IFN-beta may act by upregulating the expression of anti-inflammatory components of the immune system. OBJECTIVES: To determine whether weekly intramuscular (i.m.) injection of IFN-beta1a had a short- or long-term effect on the expression of naturally occurring soluble factors that play an immunosuppressive role within the cytokine network. MATERIALS AND METHODS: serum levels of interleukin-1 receptor antagonist (IL-1Ra), soluble tumor necrosis factor alpha receptor type I and type II (sTNF-alphaRI and sTNF-alphaRII), and soluble E-selectin (sE-Sel) were followed over time in ten patients with RRMS who were treated with weekly i.m. injections of 30 mg (= 6 MU) of IFN-beta1a. Patient sera were sampled before, and 24, 48, 72, 96, and 168 hours after the first IFN-beta1a injection (short-term), and then at 1, 3, 6, 9 and 12 months after therapy initiation (long-term); highly sensitive, commercially available ELISA tests were used. RESULTS: serum levels of IL-1Ra, sTNF-alphaRI and sTNF-alphaRII, but not sE-Sel were significantly increased in both short- and long-term follow-up. Interestingly, IL-1Ra, sTNF-alphaRI and sTNF-alphaRII behaviors were completely different, suggesting that these naturally occurring immunoregulatory factors were differentially affected by IFN-beta1a. CONCLUSION: our study demonstrates that weekly i.m. injection of 30 mg of IFN-beta1a induces the expression of soluble mediators that may suppress the activities of pro-inflammatory cytokines such as IL-1 and TNF-alpha. 相似文献
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Kraemer WJ Ratamess NA Maresh CM Anderson JA Tiberio DP Joyce ME Messinger BN French DN Sharman MJ Rubin MR Gómez AL Volek JS Silvestre R Salvestre R Hesslink RL 《Journal of strength and conditioning research / National Strength & Conditioning Association》2005,19(1):115-121
The purpose of the present investigation was to examine the effects of 30 days of treatment with a topical cream consisting of cetylated fatty acids on static postural stability and plantar pressures in patients with osteoarthritis (OA) of one or both knees. Forty patients diagnosed with knee OA were randomly assigned to 1 of 2 topical treatment groups: (a) cetylated fatty acid (CFA; N = 20; age = 62.7 +/- 11.7 years); or (b) placebo (P; N = 20; age = 64.6 +/- 10.5 years). Patients were tested on 2 occasions: (a) baseline (T1), and (b) following a 30-day treatment period consisting of cream application twice per day (T2). Assessments included 20- and 40-second quiet standing protocols on a force plate to measure center of pressure (COP) total excursion length, COP velocity, and rearfoot and forefoot plantar pressure distribution. In the CFA group, a significant reduction in the COP excursion length and velocity were observed at T2, whereas no significant differences were observed in the P group. No significant differences in mean forefoot, rearfoot, or rearfoot-to-forefoot plantar pressure ratios were observed in either group at T2. However, in a subgroup of participants designated to be right- or left-side dominant, improvements in the right-to-left forefoot plantar pressure ratios were observed in both groups. These data indicate that 30 days of treatment with a topical cream consisting of cetylated fatty acids improves static postural stability in patients with knee OA presumably due to pain relief during quiet standing. Such over-the-counter treatment may help improve the exercise trainability of people with OA. 相似文献
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Tiberio L Tiberio GA Bardella L Cervi E Cerea K Dreano M Garotta G Fra A Montani N Ferrari-Bravo A Callea F Grigolato P Giulini SM Schiaffonati L 《Cytokine》2006,34(3-4):131-142
Numerous animal studies simulating liver injury have demonstrated that interleukin-6 (IL-6) exerts a protective effect. This study was designed to further analyze the molecular mechanisms underlying the protective role of IL-6 in a rat model of liver ischemia/reperfusion injury. We show that IL-6: (i) at high doses reduces cell damage which occurs in ischemic-reperfused liver, while at low doses displays only a limited protective capacity, (ii) anticipates and enhances hepatocyte compensatory proliferation seen in ischemic-reperfused liver also at a low, more pharmacologically acceptable dose, (iii) sustains the acute phase response which is dampened in ischemic-reperfused liver, (iv) strengthens the heat shock-stress response shown by ischemic-reperfused liver and (v) overcomes the dysfunctions of the unfolding protein response found in ischemic-reperfused liver. We also show that IL-6-enhanced STAT3 activation probably plays a crucial role in the potentiation of the different protective pathways activated in ischemic-reperfused liver. Our data confirm that IL-6 is a potential therapeutic in liver injury of different etiologies and reveal novel mechanisms by which IL-6 sustains liver function after ischemia/reperfusion injury. 相似文献
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Laura Pini Laura Tiberio Narayanan Venkatesan Michela Bezzi Luciano Corda Maurizio Luisetti Ilaria Ferrarotti Mario Malerba David A Lomas Sabina Janciauskiene Enrico Vizzardi Denise Modina Luisa Schiaffonati Claudio Tantucci 《Respiratory research》2014,15(1)